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Primel – guess a 5 digit prime number – each guess must be a prime

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Re: Primel – guess a 5 digit prime number – each guess must be a prime

#11

97501 and 24683 will get you all of the numbers (and maybe some position matches), from there it becomes much easier.

Enable "hard mode" in a future release, which, like Wordle's hard mode, rejects any guesses ruled out by previous answers.

Re: Primel – guess a 5 digit prime number – each guess must be a prime

#13
post #5

Earlier quoted context omitted.

It's not a 5 digit prime.

0 is a digit. Apparently I have stumbled over an idiom of the prime-enthusiast community.

I don't think the different usage is related to an individual group rather context, particularly when referring to numbers.

E.g. 3 is a 1 digit number because that's the number of digits needed to uniquely identify 3. There are infinitely more ways to identify 3 the number with padded 0s but those aren't useful unless you're talking about combinations/sequences of groups of digits (like random numbers or PIN codes) instead of actual number values.

Re: Primel – guess a 5 digit prime number – each guess must be a prime

#16
post #5

Earlier quoted context omitted.

It's not a 5 digit prime.

0 is a digit. Apparently I have stumbled over an idiom of the prime-enthusiast community.

I don't think it's specific to "the prime-enthusiast community". Most people would look at you oddly if you claimed that 3 is a five-digit number.

Re: Primel – guess a 5 digit prime number – each guess must be a prime

#17

So are people just really good with numbers? I don't know any 5 digit primes nor do I know a way to calculate them on the fly.

I intuited a probably-inaccurate trick with exponentially raising a small prime (e.g 7*7*7etc), doubling the multiple (*2), and subtracting 1 (to get an odd number).

That got me two substantially-different primes and narrowed my numbers a lot, which then became guesswork.

My guesses in the end:

  -?---
  ?---!
  ?-??!
  ?!??!
  !!!!!

Re: Primel – guess a 5 digit prime number – each guess must be a prime

#18

12347 - 65393 ++-- [solution next - omitted for spoiler reasons] I was more surprised about how little trial and error I needed to find primes than about how few guesses it actually took...

Same, I was so surprised to get it solved at the second row, after ~8 attempts to find a prime without the numbers that had not matched.

    12347
      -
   [solved]

Re: Primel – guess a 5 digit prime number – each guess must be a prime

#20

So are people just really good with numbers? I don't know any 5 digit primes nor do I know a way to calculate them on the fly.

apparently 9.3% of all '5 digit' numbers are prime, so random guessing isn't a bad strategy - you'll find one in 10.75 totally randomly chosen numbers to be prime.

Being a little smarter, prime number can only end in a 1, 3, 7 or 9 - (ending in 0, 2, 4, 6, 8 would be even, ending in 5 would be odd), so in fact it's more like 25% of 'likely' guesses.

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